The present invention relates to a system and method for detecting and handling artifactual data in hemodynamic waveforms.
It is possible to obtain cardiovascular data, for healthcare and research purposes, using an implantable medical device (IMD) such as an implantable hemodynamic monitor (IHM), together with a pressure sensor lead that senses blood pressure within a heart chamber and an electrogram (EGM) of the heart. The IHM senses absolute blood pressure values, and the patient is also provided with an externally worn atmospheric pressure reference monitor record contemporaneous atmospheric pressure values.
A cardiovascular analysis system using the IHM can be programmed to sense and calculate various hemodynamic parameters. The IHM is programmed and interrogated employing an external programmer or a PC to accumulate trend data at a programmable resolution.
The memory buffers of the IHM and the atmospheric pressure reference monitor can transmit by telemetry the sensed and stored pressure and other data, thereby emptying the buffers, to a nearby interactive remote monitor for temporary storage of the data. The interactive remote monitor periodically transmits accumulated data to a remote data processing center that can process the data to develop trend data that the attending physician can review, along with other patient data derived in patient examinations and interviews, to assess cardiovascular health.
Such an IHM system implanted in patients suffering from adverse cardiovascular health conditions can accumulate date-stamped and time-stamped blood pressure data that can be of use in determining the condition of the heart and or vascular system over an extended period of time and while the patient is clinically tested or is engaged in daily activities. Various other IHM functions and uses of EGM, pressure and other parameter data accumulated in an IHM are disclosed in U.S. Pat. Nos. 5,368,040, 5,417,717, 5,564,434, 6,104,949, 6,155,267, 6,280,409, 6,275,707, 6,309,350, and 6,438,408, and U.S. Pat. App. Ser. Nos. 2003/0199779 and 2004/0167410.
Data collected by an IHM system may contain undesired artifactual data, in addition to desired data. Generally, artifactual data is any data corresponding to an inaccurate observation, effect, or result, especially one resulting from characteristics of the IHM system used in gathering the data or due to data collection error.